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arXiv · 1808.03091

Breakdown of effective temperature, power law interactions and self-propulsion in a momentum conserving active fluid

Amit Singh Vishen·Jacques Prost·Madan Rao
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Abstract

Simplest extensions of single particle dynamics in momentum conserving active fluid - that of an active suspension of two colloidal particles or a single particle confined by a wall - exhibit strong departures from Boltzmann behavior, resulting in either a breakdown of an effective temperature description or a steady state with nonzero entropy production rate. This is a consequence of hydrodynamic interactions that introduce multiplicative noise in the stochastic description of the particle positions. This results in fluctuation induced interactions that depend on distance as a power law. We find that the dynamics of activated colloids in a passive fluid, with stochastic forcing localized on the particle, is different from that of passive colloids in an active fluctuating fluid.

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Amit Singh Vishen, Jacques Prost, Madan Rao. 2019-11-27. Breakdown of effective temperature, power law interactions and self-propulsion in a momentum conserving active fluid. https://doi.org/10.1103/physreve.100.062602

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